本文阅读前了解知识：什么时候需要使用UrlEncode和UrlDecode函数
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作者使用谷歌浏览器，通过按下F12对第三方网站http协议的接口抓包进行分析操作。
场景
运维小哥哥偶尔使用某某外包公司的网站系统，做设备录入工作，流程简单：
录入设备信息
- 录入设备基本信息，有7、8个字段需要输入，然后点击保存按钮；
- 基本信息保存成功，进入设备类型选择操作，然后点击生成设备标识按钮；
- 设备标识生成成功，录入设备关联的模块信息，简单设备只需要录入2条模块，复杂的设备有6条模块，每个模块有3、4个字段需要输入，最后点击保存。
一条设备录入成功，单身多年的手速可能也花不了几分钟，其实这也没啥。
突然领导说有1000个设备需要搞？运维小哥哥哭了😂，这时就该开发人员上场了：
- 运维准备一个Excel模板，输入需要录入的1000个设备基本信息、设备类型信息，这个工作量不大，就半天吧，最多一天工作量；
- 开发做个C/S客户端小工具，程序中按业务要求配置模块录入规则；
- 程序执行过程中录入一个设备就把生成的设备标识与设备关联；
- 全部录入完成，提供一个Excel导出，可将设备基本信息、生成的设备标识全部关联导出，工作完成。
经过几天的开发工作，开发哥哥将精心打磨的小工具交给运维小哥，运维小哥哥使用后投来了赞许的目光…
问题
前面铺垫的话有点啰嗦了，开发这个小工具时，开发小哥遇到一个问题：
xxx接口
这是某个接口的信息，Content-Type 是 application/x-www-form-urlencoded,下面参数使用的Form Data，即参数使用了UrlEncode，比如未编码前的一个参数：
1 | ruby复制代码"Content":"{"AP_Name":"HK_7889","IP":"192.168.0.1"}" |
编码后(可以使用这个在线URL编码解码工具验证)：
1 | perl复制代码"Content":"%7B%22AP_Name%22%3A%22HK_7889%22%2C%22IP%22%3A%2292.168.0.1%22%7D" |
使用Postman测试时，未对参数使用UrlEncode，接口测试成功,开发这个小工具时，有3个接口都是类似的，未进行UrlEncode操作：
1 | vbscript复制代码var client = new RestClient("http://admin.lqclass.com/api/device");client.Timeout = -1;var request = new RestRequest(Method.POST);request.AddHeader("Content-Type", "application/x-www-form-urlencoded");request.AddParameter("Content", "{\"AP_Name\":\"HK_7889\",\"IP\":\"92.168.0.1\"}");IRestResponse response = client.Execute(request);Console.WriteLine(response.Content); |
但遇到稍微复杂一点的接口，比如截图中的参数为：
1 | sql复制代码"Content":"{"AP_Name":"HK_7889","IP":"192.168.0.1","Module":[{"M_Name":"cameri0","Desc":"cameri0","AP_PUID":"54632325461320320"},{"M_Name":"cameri1","Desc":"cameri1","AP_PUID":"54636325461320320"},{"M_Name":"cameri2","Desc":"cameri2","AP_PUID":"54632325421320320"}]}" |
Content值格式化看得清楚一点，Module是设备关联的模块信息：
1 | json复制代码{ "AP_Name": "HK_7889", "IP": "192.168.0.1", "Module": [ { "M_Name": "cameri0", "Desc": "cameri0", "AP_PUID": "54632325461320320" }, { "M_Name": "cameri1", "Desc": "cameri1", "AP_PUID": "54636325461320320" }, { "M_Name": "cameri2", "Desc": "cameri2", "AP_PUID": "54632325421320320" } ]} |
实际UrlEncode后的参数为：
1 | perl复制代码"Content":"%7B%22AP_Name%22%3A%22HK_7889%22%2C%22IP%22%3A%22192.168.0.1%22%2C%22Module%22%3A%22%255B%257B%2522M_Name%2522%253A%2522cameri0%2522%252C%2522Desc%2522%253A%2522cameri0%2522%252C%2522AP_PUID%2522%253A%252254632325461320320%2522%257D%252C%257B%2522M_Name%2522%253A%2522cameri1%2522%252C%2522Desc%2522%253A%2522cameri1%2522%252C%2522AP_PUID%2522%253A%252254636325461320320%2522%257D%252C%257B%2522M_Name%2522%253A%2522cameri2%2522%252C%2522Desc%2522%253A%2522cameri2%2522%252C%2522AP_PUID%2522%253A%252254632325421320320%2522%257D%255D%22%7D" |
本来一般接口，如上面成功执行的C#代码那般直接未UrlEncode调用是没问题的。
但这个接口调用，服务器返回错误信息：“xxx解析失败”，调用代码如下：
1 | swift复制代码var client = new RestClient("http://admin.lqclass.com/api/device");client.Timeout = -1;var request = new RestRequest(Method.POST);request.AddHeader("Content-Type", "application/x-www-form-urlencoded");request.AddParameter("Content", "{\"AP_Name\":\"HK_7889\",\"IP\":\"192.168.0.1\",\"Module\":[{\"M_Name\":\"cameri0\",\"Desc\":\"cameri0\",\"AP_PUID\":\"54632325461320320\"},{\"M_Name\":\"cameri1\",\"Desc\":\"cameri1\",\"AP_PUID\":\"54636325461320320\"},{\"M_Name\":\"cameri2\",\"Desc\":\"cameri2\",\"AP_PUID\":\"54632325421320320\"}]}");IRestResponse response = client.Execute(request);Console.WriteLine(response.Content); |
两处调用代码哪里不同？只是Content值不一样，最后怀疑是不是需要手动进行UrlEncode？又不是url参数，为啥需要编码呢？不管啦，先编码了再说。
问题解决
参数编码后，调用：
1 | perl复制代码var client = new RestClient("http://admin.lqclass.com/api/device");client.Timeout = -1;var request = new RestRequest(Method.POST);request.AddHeader("Content-Type", "application/x-www-form-urlencoded");request.AddParameter("Content", "%7B%22AP_Name%22%3A%22HK_7889%22%2C%22IP%22%3A%22192.168.0.1%22%2C%22Module%22%3A%22%255B%257B%2522M_Name%2522%253A%2522cameri0%2522%252C%2522Desc%2522%253A%2522cameri0%2522%252C%2522AP_PUID%2522%253A%252254632325461320320%2522%257D%252C%257B%2522M_Name%2522%253A%2522cameri1%2522%252C%2522Desc%2522%253A%2522cameri1%2522%252C%2522AP_PUID%2522%253A%252254636325461320320%2522%257D%252C%257B%2522M_Name%2522%253A%2522cameri2%2522%252C%2522Desc%2522%253A%2522cameri2%2522%252C%2522AP_PUID%2522%253A%252254632325421320320%2522%257D%255D%22%7D");IRestResponse response = client.Execute(request);Console.WriteLine(response.Content); |
其实中间还做了一个参数的UrlEncode操作，即下面的Module参数值：
1 | css复制代码"Content":{"AP_Name":"HK_7889","IP":"192.168.0.1","Module":[{"M_Name":"cameri0","Desc":"cameri0","AP_PUID":"54632325461320320"},{"M_Name":"cameri1","Desc":"cameri1","AP_PUID":"54636325461320320"},{"M_Name":"cameri2","Desc":"cameri2","AP_PUID":"54632325421320320"}]} |
第一次UrlEncode，即先对Module的值进行UrlEncode：
1 | perl复制代码"Content"：{"AP_Name":"HK_7889","IP":"192.168.0.1","Module":%5B%7B%22M_Name%22%3A%22cameri0%22%2C%22Desc%22%3A%22cameri0%22%2C%22AP_PUID%22%3A%2254632325461320320%22%7D%2C%7B%22M_Name%22%3A%22cameri1%22%2C%22Desc%22%3A%22cameri1%22%2C%22AP_PUID%22%3A%2254636325461320320%22%7D%2C%7B%22M_Name%22%3A%22cameri2%22%2C%22Desc%22%3A%22cameri2%22%2C%22AP_PUID%22%3A%2254632325421320320%22%7D%5D} |
第二次UrlEncode即是上面成功的参数方式了，对整个Content的值进行UrlEncode，看上面成功的参数，不重复贴了。
最后总结
抓别人数据包时，不要凭印象、已有知识判定该怎么怎么做，比如前面的参数，不使用UrlEncode时，调用成功了，其他包我是否也沿用相同的方式使用就正确呢？搞不定时，多尝试猜测的方法。
总结：“管他的，干就是了”。
本文使用的UrlEncode C# 代码：
1 | vbnet复制代码public static string UrlEncode(string str){ StringBuilder sb = new StringBuilder(); byte[] byStr = System.Text.Encoding.UTF8.GetBytes(str); //默认是System.Text.Encoding.Default.GetBytes(str) for (int i = 0; i < byStr.Length; i++) { sb.Append(@"%" + Convert.ToString(byStr[i], 16)); } return (sb.ToString());} |
本文转载自: 掘金
